DE29715732U1 - Arrangement to secure a key opening against unauthorized access or vandalism - Google Patents

Abstract

The closure cap (4) covering the key hole (11) forms a hollow cavity (6) connected by an opening (7,8) with the front side (7) of the closure cap, in the extension of the key hole with a door leaf (2). The closure cap contains a security element (5) tapering towards the lock (1) and which locks with a rotary movement, for covering the key hole. The security element has at least one locking plate spring (22) which has arms shaped into runners. The opening has slotted wider parts for inserting the locking spring into the hollow cavity. A track (14) inside the cap is open towards the hollow cavity.

Description

Hans-Jürgen Müller Gerhard D. Schupfner

&tgr;^&khgr;^; ⁴ 9 ⁹ :8 ⁸ 9 ⁹ --2 ² &iacgr;^:2^&ogr; Hans-Peter Gauger

e-mail: upon request PO Box 10 11 61 Patent Attorneys

Telegram/cable: Maximilianstraße 6 European Patent Attorneys

MAXIMARK® Munich D-80085 Munich Representatives and European licenses

HJM/MY

Electrowatt

Technology Innovation AG

CH-6301 Zug
Switzerland

"Order to secure a key opening against unauthorized access or vandalism"

MAXIMARKFonnOl

Arrangement for securing a key opening of a lock against unauthorized access or vandalism

The innovation relates to an arrangement for securing a key opening of a lock against unauthorized access or vandalism according to the preamble of claim 1.

The arrangement is used for locking devices of all kinds that require special protection against unauthorized access and especially against vandalism, for example cash boxes of cash register units installed in public and in a wide variety of vending machines, especially safes in coin-operated telephone machines.

An arrangement of the type mentioned at the beginning is known from EP-A 754'828. A locking cap is arranged in front of a key opening of a lock and allows the lock to be operated with a key inserted through a cylindrical opening in the locking cap. A locking cylinder that fits into the cylindrical opening of the locking cap is equipped at one end with a locking pin arranged transversely to the cylinder axis. To secure the lock, the locking cylinder is inserted into the opening of the locking cap with the locking pin first, whereby the locking pin is pushed through a slot-shaped recess in a plate arranged in the depth of the opening in the locking cap. When the locking cylinder rotates around its own axis with the help of a key, the locking pin engages behind the plate with the slot-shaped recess and engages in locking springs arranged behind the plate.

This device has the disadvantage that the torque for securing and unlocking is practically the same, so that the lock can also be unlocked by unauthorized persons using a locking cap that moves easily when securing.

The innovation is based on the task of creating a locking cap for securing a lock in which the torque when unlocking is several times greater than when securing.

The above object is achieved according to the invention by the features specified in the characterizing part of claim 1. Advantageous embodiments of the innovation emerge from the dependent claims.

An embodiment of the innovation is shown in the drawings and is described in more detail below.

Figure 1 shows a cross section through a door with lock and locking cap as well as with

an unused safety element,

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figure 3 figure 4 figure 5 figure 6 figure 7 figure 8th figure 9 figure 10

Figure 2 a front view of the closure cap without the safety element inserted,

the securing element,

the locking element rotated 90° around its axis, the locking element in the closure cap, another form of the locking element,

a cross-section through the closure cap with the inserted locking element,

a development of a slideway with skids in position 0° Figure 9 like Figure 8, but with skids in position 90° and

as figure 8, but with skids in position 180°.

In Figure 1, 1 means a lock, 2 a door leaf of a safe door, 3 an opening in the door leaf 2, 4 a closure cap placed on the outside of the door leaf 2 and 5 a security element. Between the closure cap 4 and the door leaf 2, a recess in the closure cap 4 forms a cylindrical cavity 6, which is connected via a passage 7 to a cylindrical recess 8 on the front surface 9 of the closure cap 4. A housing 10 of the lock 1 has a keyhole 11 in order to insert a key (not shown here) to operate the lock 1. The keyhole 11, the cavity 6, the passage 7 and the cylindrical recess 8 have a common axis 12. The cavity 6 and the recess 8 have the same inner radius R1, while the passage 7 has a smaller inner radius R2. The transition from the recess 8 to the passage 7 forms a step 13 parallel to the front surface 9. The extension from the passage 7 to the cavity 6 serves as a slideway 14, also essentially parallel to the front surface 9. The surfaces of the step 13 and the slideway 14 are smoothed. As described in the patent application EP-A 754'828, the closure cap 4 is placed on the door leaf 2 and riveted or, if the door leaf 2 is sufficiently thick, integrated directly into the door leaf 2.

The body of the securing element 5 is advantageously composed of two coaxial cylinders 15, 16, where the first cylinder 15 with the smaller radius fits into the passage 7 with little play and the second cylinder 16 with the larger radius fits into the recess 8 with little play. The height of the second cylinder 16 is advantageously dimensioned such that when the second cylinder 16 sits on the shoulder 13, the top 17 of the second cylinder 16 is flush with the front surface 9. The transition between the two cylinders 15, 16 forms a circular ring surface 18 parallel to the top 17

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The second cylinder 16 has a blind hole 19 with a slightly elliptical cross-section in the top side 17, which can accommodate a correspondingly shaped pin 20 of an assembly key 21. Designs of the assembly key 21 and the blind hole 19 are described in the patent application EP-A 754'828 mentioned at the beginning.

The lower end of the securing element 5 has at least one locking spring 22 designed symmetrically to the axis 12, the arms of which protrude beyond the outer surface of the first cylinder 15 and, measured from the axis 12, are slightly smaller than the inner radius Rl of the recess 8. To secure the lock, the securing element 5 is pushed into the recess 8 with the locking springs 22 leading.

The lock 1 is located on the inside of the door leaf 2 and can be easily replaced when the safe door is open.

Figure 2 shows the top view of the front surface 9 of the closure cap 4. As a passage for the arms of the locking spring 22 (Figure 1), the passage 7 has slot-shaped extensions 23, 24 from the inner radius R2 to the inner radius Rl, which connect the cavity 6 (Figure 1) with the recess 8 and are so wide that when the locking element 5 is pushed in (Figure 1), the arms of the locking spring 22 at the lower end of the locking element 5 penetrate through the slot-shaped extensions 23, 24 into the cavity 6. To secure the keyhole 11, the locking element 5 can therefore be pushed completely into the recess 8 until the circular ring surface 18 (Figure 1) rests on the shoulder 13 and the surface 17 (Figure 1) is flush with the front surface 9.

Figure 3 shows a view of the securing element 5 with the locking spring 22. The first cylinder 15 has, for example, claws 25 arranged symmetrically to the axis 12 on the free cover surface, with which the locking spring 22 is held laterally and overlapping it in a rotationally secure manner. It is also conceivable to have a mandrel with a square cross-section penetrating the locking spring 22, which engages in the locking spring 22 in a form-fitting manner and is riveted, screwed or otherwise fastened to it.

The example of the locking element 5 shown here is set up for a right-hand rotation, i.e. it is rotated clockwise (direction of an arrow 26 on the outer surface of the cylinder 16) when looking at the top 17. The locking spring 22 has two arms with the skids 27, 28, which can hold the locking element 5 in the closure cap 4 (Figure 1). The locking spring 22 is deformed in the area of the slideway 14 (Figure 1) to form the skids 27, 28, with the two edges of the locking spring 22 that are in front in the direction of rotation being bent away from the first cylinder 15. In the drawing in Figure 3, the front edge on the right and the rear edge on the left of the locking spring 22 are raised like a slide.

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In Figure 4, the securing element 5 is shown after a clockwise rotation of 90° around the axis 12. The new position of the arrow 26 on the outer surface of the second cylinder 16 is intended to indicate this. The design of the skids 27, 28 is now clearly visible. The skids 27, 28 enable the locking spring 22 to run onto the slideway 14. For reasons of elasticity, two thinner spring plates, the locking spring 22 and a flat spring leaf 22a, are advantageously used instead of a single thick locking spring 22, with the locking spring 22 with the skids 27, 28 being arranged between the spring leaf 22a and the free circular surface of the first cylinder 15. The claws 25 hold the locking spring 22 and the spring leaf 22a together and prevent the two spring leaves from twisting relative to the first cylinder 15.

Figure 5 shows the view from the cavity 6 (Figure 1) of the inserted securing element 5 (Figure 1). The slideway 14 (Figure 1) is divided into four flat sections 29, 29', 31, 31', of which the plane with the opposite sections 29, 29' and 31, 31' are at different distances measured from the front side 9 (Figure 1). The sections 29 and 31 and the sections 31 and 29' are separated by the extension 23 and 24, respectively, and a locking field 30 is arranged between the sections 29 and 31 and a locking field 30' is arranged between the sections 29' and 31'. The base of the two locking fields 30, 30' are incorporated into the material of the closure cap 4 at least by the thickness of the locking spring 22 deeper than the level of the first sections 29, 29'. The locking spring 22 is here in a different design inserted into a groove 32 in the first cylinder 15 and secured with a screw 33. When the locking element 5 was inserted, the locking spring 22 was aligned along the line A-A'. After the locking element 5 has been turned 90° to the right, the sliding skids 27, 28 are engaged in the locking fields 30, 30', so that the locking element 5 is anchored in the closure cap 4.

In Figure 6, the cross section A-A' (Figure 5) illustrates the design of the slideway 14 (Figure 1). The planes of the sections 29 and 31 of the slideway 14 visible here and the dotted plane of the locking field 30 are parallel. The plane of the locking field 30 is closest to the front side 9 and the plane of the second section 31 is furthest away from the front side 9.

The securing element 5 here has the special shape of a truncated cone with the axis 12, which is inserted into a correspondingly shaped opening in the closure cap 4 of the door leaf 2 and which extends from the front side 9 to the cavity 6. The opening expands evenly from the inner radius R2 at the transition to the cavity 6 to the value of the inner radius Rl on the front side 9.

Figure 7 shows the closure cap 4 in cross section with the inserted securing element 5 according to the design of Figure 1. When inserting the securing element 5, the sliding skids 27 (Figure 1), 28 of the locking spring 22 are pushed through the extensions 23, 24 of the passage 7 (Figure 1) into the cavity 6. As soon as the surface 17 is flush with the front side 9, the sliding skid 28 runs over a run-up edge 29a when the securing element 5 is rotated to the right about the axis 12.

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onto the first section 29' of the slideway 14, whereby the locking spring 22 is tensioned. The sliding skid 28 then slides on the first section 29'. After completing the right rotation of 90°, the locking spring 22 partially relaxes because the sliding skid 28 sinks to the bottom of the locking field 30', which is lower than the first section 29'. In this position shown in Figure 7, the locking element 5 is secured in the closure cap 4. When unlocking, it is necessary to continue turning in the same direction so that the sliding skid 28 is raised to the height of the second section 31'. A much greater torque is required for this than when securing, since the locking spring 22 undergoes a greater deflection (deflection). The sliding skid 28 slides on the second section 3 &Ggr; until the extension 24 is reached. As soon as the skid 28 with the skid end 34 slides over a section end 35' of the second section 31', the locking spring 22 snaps into its rest position and relaxes. The safety element 5 is released and can be removed from the closure cap 4. The lock 1 (Figure 1) is now released for operation.

The corresponding process also takes place simultaneously for the parts with the reference numbers 27, 29, 29b, 30, 31, 34 and 35 that are cut away in the illustration in Figure 7 and are therefore not visible.

Figures 8 to 10 show the development of the outer surface 36, 36' of the passage 7 (Figure 1) with the profile of the slideway 14 (Figure 1) as a function of the angle of rotation α with the three important positions of the slide skids 27, 28 and illustrate the process of securing and unlocking the lock 1 (Figure 1). Since the development repeats itself after 360°, these parts are shown in dotted lines.

In Figure 8, the securing element 5 (Figure 7) is fully inserted into the opening of the closure cap 4 (Figure 7) for securing, whereby the sliding skids 27, 28 reach the cavity 6 through the extensions 24, 23. The slide shape of the sliding skids 27, 28 is selected so that when they are turned to the right, i.e. in the direction of positive angles, they are easily raised by the drive-on edges 29a, 29b onto the first sections 29, 29', whereby the locking spring 22 (Figure 7) is put under tension. A left turn, i.e. in the direction of a negative angle, is impossible due to the lack of a bend at the sliding skid end 34, 34' of the sliding skids 27, 28, since the sliding skid ends 34, 34' of the vertical wall of the extension 23 and 24 are at the end of the section 35 and 35' and lifting the sliding skids 27, 28 onto the slideway 14 is therefore impossible. As soon as the angle of rotation α = 90° is reached, the sliding skids 27, 28 snap into the locking fields 30, 30', whereby the locking spring 22 is partially released.

Figure 9 shows the situation of the skids 27, 28 with a safety element 5 secured in the closure cap 4 (Figure 7). The usual left turn to release the safety element 5 is not possible, since the skid ends 34, 34' immediately come into contact with the vertical boundaries of the locking fields 30, 30' when attempting to turn left, and a further

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Prevent left-hand rotation. To release the safety element 5, it must necessarily be turned further to the right. The skids 27, 28 must be raised to the height of the second sections 31, 31', whereby the locking spring 22 (Figure 7) is tensioned much more than during the securing process. The torque required to release is therefore very high and gives an unauthorized person the impression that the safety element 5 is being released in a different way. This improvement compared to the device from the patent application EPA 754'828 mentioned at the beginning already deters most unauthorized persons from making further attempts. The necessary torque can only be applied with a positive-locking assembly key 21 (Figure 1). When rotating to the right, the skids 27, 28 slide on the second sections 31, 31' in the direction of the angle of rotation α. = 180°.

In Figure 10, the skids 27, 28 have reached the extensions 23, 24 and the securing element 5 (Figure 7) can be removed from the closure cap 4 (Figure 7).

In a practical embodiment according to Figure 1, the closure cap 4 is riveted to the door leaf 2. The height of the cylindrical closure cap 4 is 20 mm and its diameter is 75 mm. The inner radius Rl (Figure 2) of the recess 8 and the inner radius R2 (Figure 2) of the passage 7 have the values 23.0 mm and 15.3 mm. The step 13 is lowered by 6.0 mm from the front plate 9. The plane of the first sections 29, 29' (Figure 8) of the slideway 14 is 13.2 mm from the front plate 9, while the plane of the second sections 31, 31' is further away from the front plate 9 at 14.2 mm. The bottom of the locking fields 30, 30' is 12.0 mm from the front plate 9. The second cylinder 16 of the safety element 5 has a clearance of 0.5 mm in the recess 8 and the first cylinder 15 is 0.6 mm narrower in diameter than the passage 7. The plane of the locking spring in the relaxed state is 11 mm from the surface 17. The locking spring 22 in Figure 5 is 12 mm wide and measures 44 mm in length overall.

Instead of the two-armed locking spring 22 described here, three-, four- or multi-armed locking springs 22 can also be used. The multi-armed locking springs 22 require a finer subdivision of the slideway 14 and an increase in the number of extensions 23, 24.

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Claims (7)

EXPECTATIONS 1. Arrangement for securing a lock (1) against unauthorized access or vandalism, with a closure cap (4) covering a key opening (11), which, in extension of the key opening (11), forms with a door leaf (2) a cavity (6) which is connected to a front side (7) of the closure cap (4) via an opening (7, 8) and which positively receives a security element (5) which is to be locked with a rotary movement and tapers towards the lock (1) to cover the key opening (11), characterized in that that the securing element (5) has at least one leaf-shaped locking spring (22, 22a) secured against rotation on its tapered side, that arms of the locking spring (22) projecting beyond the tapered side of the securing element (5) are deformed into sliding skids (27; 28),
that the opening (7) has slot-shaped extensions (23; 24) for inserting the locking spring (22, 22a) into the cavity (6) and that a slideway (14) formed in the closure cap (4), open towards the cavity (6) and interrupted by the extensions (23; 24) is designed in such a way that after a predetermined rotation of the securing element (5) inserted into the closure cap (4), the slide skids (27; 28) have run onto first sections (29; 29') under tension of the locking spring (22, 22a) and, engaging behind the opening (7), hold the securing element (5) in the opening (7, 8). 2. Arrangement according to claim 1, characterized in that the slideway (14) has recessed locking fields (30; 30') offset by 180° for receiving the sliding skids (27; 28) after a predetermined angle of rotation, that the locking fields (30; 30') are shaped in such a way that in order to release the securing element (5), the sliding skids (27; 28) snapped into the locking fields (30; 30') can only be moved to the extensions (24; 23) by rotating in the same direction of rotation over second sections (31; 3 P) of the slideway (14). 3. Arrangement according to claim 2, characterized in that the locking spring (22, 22a) has a greater deflection on the second sections (31; 3P) than on the first sections (29; 29'). 4. Arrangement according to one of claims 1 to 3, characterized in that the body of the safety element (5) comprises two cylinders (15; 16) with different diameters, whereby the second cylinder (16) with the larger diameter on its free surface (17) P2857 at least one blind hole (19) recessed into the securing element (5) for receiving form-fitting pins (20) of an assembly key (21). 5. Arrangement according to one of claims 1 to 3, characterized in that the body of the securing element (5) is a truncated cone, the circular surface (17) of which with the larger diameter has at least one blind hole (19) let into the securing element (5) for the reception of form-fitting pins (20) of an assembly key (21). 6. Arrangement according to one of claims 1 to 5, characterized in that the outer surface (17) of the securing element (5) inserted into the closure cap (4) is flush with the front side (9) of the closure cap (4). 7. Arrangement according to one of claims 1 to 6, characterized in that the closure cap (4) is integrated into the door leaf (2). P2857